// 改改指针的值，更改指针所指向对象的值
#include <iostream>

int main()
{
    int a = 2, b = 4;
    int *pI;
    pI = &a;

    *pI = 3; // 此时a = 3;
    std::cout << a << std::endl;
    pI = &b;
    std::cout << *pI << std::endl;
}